Estou tentando dividir meu layout em 3 linhas iguais, tentando usar LinearLayout e pesos, mas não funciona, não faz nenhuma alteração:

<LinearLayout
    android:id="@+id/rightLayout"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_alignBottom="@+id/picture"
    android:layout_alignParentRight="true"
    android:layout_alignTop="@+id/picture"
    android:layout_toRightOf="@+id/aligner"
    android:orientation="vertical"
    android:weightSum="3" >

    <LinearLayout
        android:id="@+id/lay1"
        android:layout_width="fill_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:background="#00ff00" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/lay2"
        android:layout_width="fill_parent"
        android:layout_height="0dip"
        android:layout_weight="1" >

        <TextView
            android:id="@+id/TextView01"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/lay3"
        android:layout_width="fill_parent"
        android:layout_height="0dip"
        android:layout_weight="1" >

        <TextView
            android:id="@+id/TextView02"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />
    </LinearLayout>

</LinearLayout>